Membrane-type carriers are one type of device used to electrically connect surface-mounted integrated circuits to circuit testers after fabrication of the integrated circuit. A membrane-type carrier normally comprises a series of contacts, usually conductive pads, for making a temporary electrical connection with the surface-mounted integrated circuit. These contacts are electrically connected to terminals on the carrier. Carrier terminals ordinarily comprise a conductive pad or a plated-through hole in the membrane carrier. Circuit testers frequently use these terminals to electrically connect the carrier to additional circuitry on a tester board designed for testing a particular type of integrated circuit.
When the tester is operational the tester apparatus connects the integrated circuit being tested to the tester board by applying mechanical pressure to the part after placing it on top of the contacts of the membrane carrier. When testing is complete, the tester apparatus removes the integrated circuit and replaces it with another integrated circuit.
The membrane carrier flexes back and forth due to the placement of integrated circuits onto the carrier under mechanical pressure, followed by their removal. After a number of repetitions, this flexing can either cause one or more tears in the membrane carrier, or damage to the contacts or terminals. Because the tester board, to which the membrane carrier is attached, is normally an expensive board to manufacture, the user of the tester will normally replace the membrane carrier rather than discarding the tester board in favor of a new tester board. When a membrane carrier wears out, either the tester remains idle while a technician replaces the membrane carrier or a spare board must be used while a technician repairs the board with the damaged membrane carrier.
The terminals of a membrane carrier often are soldered to the test board using some type of metallic pin. When replacing a membrane carrier in such a board, one must unsolder the old carrier and solder a new carrier into the test board. This process can be expensive due to both the labor costs of technician time and the potentially large number of leads on a modern integrated circuit. Spare tester boards and tester down time also can be a significant expense.